Electric control means for selfacting buckets



Oct. 28, 1947. P. JEAN-MARIE T. ALLARID 2,429,908

ELECTRIC CONTROL'MEANS FOR SELF-ACTING BUCKETS Filed May 15', 1945 2 Sheets-Sheet 1 VENTOE,

Oct. 28, 1947. P. JEAN-MARIE T. ALLARD 0 ELECTRIC CONTROL MEANS FOR SELF-ACTING BUCKETS Filed May 15; 1945 2 Sheets-Sheet 2 (L mt 42w ATT Y.

Patented Oct. 28, 1947 ELECTRIC CONTROL MEANS FOR SELF- ACTING BUCKETS Pierre Jean-Marie Theodore Allard, Chantilly,

France, assignor to Societe Francaise de Construction de Bennes Automatiques, Persan, Seine-et-Oise, France Application May 15, 1945, Serial No. 593,825 In France December 11, 1943 6 Claims.

This invention is concerned with arrangements for the electric control of self-acting grab buckets operated by a single hoisting cable or rope and an opening head or crown; the invention refers more particularly to self-acting buckets, in which the driving mechanism of the plant is operated by electric means which are acted upon by two lever systems or the like, respectively actuated by the bucket head or crown and by the slack of the hoisting rope or cable.

In the known arrangements of this kind, said lever systems both operate a common reversing switch disposed in the vicinity of the end of the bucket runway adjacent to the winch and the lever system operated by the bucket opening head or crown is connected by a rope or chain to said head or crown and to the lever system operated by the hoisting rope or cable.

However, difiiculties are encountered in providing a joint action of the two lever systems on a common electric reversing switch which will be satisfactory and reliable. On the other hand, the filling station of the bucket is often situated a long distance away from the end of the guiderunway which is adjacent to the reversing switch;

this calls for a mechanical connection of great length between the bucket head or crown and the reversing switch; such connection is, in certain cases, difficult to devise.

This invention has for its object to devise a control arrangement of the type referred to which is of a much simpler construction and avoids the defects above indicated.

The arrangement according to the invention comprises two distinct reversing switches, one being controlled by the slack of the hoisting rope or cable and the other being operated by the opening head or like.

Further features of the invention will be apparent from the following description, with reference to the accompanying drawings, which show, by way of example, three embodiments of the invention, and in which:

Fig. 1 is a diagrammatic elevational view showing an embodiment of the invention as applied to a self-acting grab bucket, the trolley of which travels on an inclined guide-runway;

Fig. 2 shows a modification in the system of levers operated by the bucket opening head or crown.

Fig. 3 shows a modification in the lever system operated by the hoisting rope or cable,

Referring to Fig. 1, the hoisting apparatus comprises an inclined guide-runway I, on which travels a trolley 2 carrying a bucket head or crown 2 3 of any suitable design, through which passes the hoisting rope or cable 4 of the grab bucket 5. The rope 4 passes over a sheave 6, carried by trolley 2, and around another sheave i, mounted at the higher end of the guide-runway I, and is then wound around the drum of a winch 8 operated by a suitable electrical motor (not shown).

At its lower end, runway I is provided with an abutment 9, located above the dumping station for stopping trolley 2, and a resilient abutment II] for stopping the trolley 2 above the filling station, the spring I I of said abutment being of such tension as to yield to an abnormal overload; in this case, the rod I2 of abutment I0 is moved in the direction of arrow J, under the traction exerted on trolley 2 by hoisting rope 4, and opens a switch I3 adapted to cut oif the supply of electric current to the whole plant.

The control arrangement according to the invention comprises a lever I4, pivoted at I5 to runway I, and provided at its free end with a counterweight I6. This lever I4 is adapted to V bear on the bucket head or crown 3, when trolley at l9 to the guide-runway I,

2 is above the filling station, and it is connected by a rope or chain I! to a second lever I8, pivoted This second lever I8 is adapted to rock down under the action of the counterweight 20 when rope I! is slack, and. to act on a reversing switch 2|, for reversing the direction of rotation of the motor operating winch 8.

A right-angular lever 22, pivoted at 23.to the higher end of guide-runway I and provided at one end with a sheave 24, bearing on the hoisting rope 4, and at the opposite end with a counterweight 25, is adapted to rock when the rope 4 is slack and to act on a second reversing switch 26 for again reversing the direction of rotation of the motor operating winch 8.

The operation is as follows:

Trolley 2 being in the position shown in Fig. 1 and bucket 5 being filled, winch 8 is operated in such a direction as to raise bucket 5 and cause it to engage bucket head 3. Continued traction on cable 4 has for its effect to raise head 3 and lever I4, whereby rope Il becomes slack and lever I8 rocks down, thus actuating switch 2| and reversing the direction of rotation of winch 8.

Trolley 2 then travels down along the runway I, under the action of its weight and the weight of the filled bucket 5. At the lower end of run- 3 reverses the direction of rotation of winch 8, through switch 26.

Now, trolley 2 and bucket suspended from crown 3 .and open, are towed along by rope 4 and travel up runway l until trolley 2 engages abutment IE]; head 3 being then in its raised position again comes into contact with lever M, which had resumed its lower position, and is raised again. Lever I8 once more Operates switch 2|, whereby the direction of rotation of winchfl is reversed, bucket 5 gets loose from head 3 and drops down, whereby head 3 and lever 14 resume their lower inoperative position. When bucket 5 reaches the goods to be taken in, rope 4 becomes slack and, through the medium of sheave 24 and switch 2%, the direction of rotation of the winch is again reversed; the whole apparatus is then ready for a further cycle.

Fig. 2 shows a modification in which lever I4 directly acts on switch 2i through a projection 21 (the lever 18 being dispensed with). The free end of lever M may .be guided in a support 28 carried by runway I.

In the modification of Fig. 3, right-angular lever 22 is replaced by a lever 29, located in the vicinity of winch 8 and having a counterweight 3B. Said lever is secured toa swinging sector 3|, which carries a roller 32, adapted to bearon rope '4. When rope 4 becomes slack, sector 31, lever '29 and counterweight 30 swing bodily in the diplant.

Obviously, the invention is not limited to the embodiments described and shown, whichhave been selected merely by way of example.

Having now described my invention what I claim as new and desire to secure by Letters 'Patent is:

'1. In a hoisting device, a runway, a trolley adapted to travel along said runway, a bucket, a hoisting cable for said bucket adapted to be guided on said trolley, a winch for said hoisting cable, a head suspended from said trolley and adapted to be raised by said bucket, abutments for stopping said trolley at the filling and dumping stations, two distinct reversing switches adapted to control rotation of said winch, means responsive to the tension of said hoisting cable for actuating oneci said switches and means responsive to upward movement of said head for actuating the other of said switches.

2. A deviceas claimed in claim 1, wherein said tension responsive means comprises a counterweight lever and a sheave carried by said lever and urgedagainst said cable by said counterweight.

3. ,A device as claimed in claim 1, wherein said tension responsive means comprises a counterweight sector and a roller carried by said sector and urged against said cable by said counterweight.

4. A device as claimed in-claim 1, wherein said upward movement responsive means comprises a counterweight leverpivoted '-to said runway.

5. A device as claimed in claim 1, wherein said upward movement responsive means comprises two comiterweight levers, pivoted-to said runway, one of said levers engaging said head and the other lever controlling said first named switch, and a flexible connection between said levers.

'6. A-device as claimedin claim 1, further comprising a out 01f switch adapted to be operated by said tension responsive means when the slack of .said cable exceeds a-predetermined limit.

PIERRE JEAN-MARIE THEODORE ALLA-RD.

REFERENCES CITED The following references are .of record in the file-of this patent:

UNITED STATES PATENTS Number Name Date 749,198 Johnson .Jan. 12, 1904 2,263,482 Allard Nov. 18, .1941 

